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The serious wear problem of heavy-haul freight vehicle wheels affects the safety and economy of vehicle operation. This paper aims to study wheel wear evolution law and the influence of line parameters on wheel wear of heavy-haul freight, and provide the basis for operation and line maintenance.

The wheel wear test data of heavy-haul freight vehicles were analyzed. Then a heavy-haul freight vehicle dynamic model was established. The line parameters influencing wheel wear in heavy-haul freight vehicles were also analyzed by the Jendel wear model, and the effects of rail cant, rail gauge, rail profile and line ramp on wheel wear were analyzed.

A rail cant of 1:40 results in less wheel wear; an increase in the rail gauge can reduce wheel wear; and when matched with the CHN60 rail, the wear depth is relatively small. A decrease of 9.21% in wheel wear depth when matched with the CHN60 rail profile. The ramp of the heavy-haul line is necessary to consider for calculating wheel wear. When the ramp is considered, the wear depth increases by 8.47%. The larger the ramp, the greater the braking force and therefore, the greater of the wheel wear.

This paper first summarizes the wear characteristics of wheels in heavy-haul freight vehicles and then systematically analyzes the effect of line parameters on wheel wear. In particular, this study researched the effects of rail cant, rail gauge, rail profile and line ramp on wheel wear.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2024-0038/

To assess the introduction and performance of light electric freight vehicles (LEFVs), more specifically cargo cycles in major 3PL organizations in at least two Nordic countries.

Case studies. Interviews. Company data on performance before as well as after the introduction. Study of differing business models as well as operational setups.

The results from the studied cases show that LEFVs can compete with conventional vans in last mile delivery operations of e-commerce parcels. We account for when this might be the case, during which circumstances and why.

Inherent limitations of the case study approach, specifically on generalization. Future research to include more public–private partnership and multi-actor approach for scalability.

Adding to knowledge on the public sector facilitation necessary to succeed with implementation and identifying cases in which LEFVs might offer efficiency gains over more traditional delivery vehicles.

One novelty is the access to detailed data from before the implementation of new vehicles and the data after the implementation. A fair comparison is made possible by the operational structure, area of delivery, number of customers, customer density, type of packages, and to some extent, the number of packages being quite similar. Additionally, we provide data showing how city hubs can allow cargo cycles to work synergistically with delivery vans. This is valuable information for organizations thinking of trying LEFVs in operations as well as municipalities/local authorities that are interested.

The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system. This paper aims to define and substantiate the assessment of the structural integrity and dynamical integrity of high-speed trains in both theory and practice. The key principles and approaches will be proposed, and their applications to high-speed trains in China will be presented.

First, the structural integrity and dynamical integrity of high-speed trains are defined, and their relationship is introduced. Then, the principles for assessing the structural integrity of structural and dynamical components are presented and practical examples of gearboxes and dampers are provided. Finally, the principles and approaches for assessing the dynamical integrity of high-speed trains are presented and a novel operational assessment method is further presented.

Vehicle system dynamics is the core of the proposed framework that provides the loads and vibrations on train components and the dynamic performance of the entire vehicle system. For assessing the structural integrity of structural components, an open-loop analysis considering both normal and abnormal vehicle conditions is needed. For assessing the structural integrity of dynamical components, a closed-loop analysis involving the influence of wear and degradation on vehicle system dynamics is needed. The analysis of vehicle system dynamics should follow the principles of complete objects, conditions and indices. Numerical, experimental and operational approaches should be combined to achieve effective assessments.

The practical applications demonstrate that assessing the structural integrity and dynamical integrity of high-speed trains can support better control of critical defects, better lifespan management of train components and better maintenance decision-making for high-speed trains.

The purpose of this paper is to develop a capacitance vehicle weighing device. The key part of this device is the capacitance vehicle weighing sensor. This paper discusses the static and dynamic performance test of capacitance vehicle weighing sensor with emphasis, and provides theoretical analysis, in order to provide the tests and theoretical basis for the popularization and application of the vehicle weighing device.

The paper gives an introduction to the weighing sensor in respects of the structure design and measuring principles, with the emphasis on the static and dynamic performance of the testing processes. Then, the paper provides the corresponding testing processes and data with theoretical analysis.

This weighing sensor can be applied to static as well as dynamic tests thus the capacitance vehicle weighing device is practical and worthy of promotion and popularization.

The capacitance vehicle weighing device is characterized by its simple structure, simple measuring circuits, strong reliability in anti‐interference, small size and low cost. The static performance is of little repetitive error, and the use of software may efficiently solve the problems of non‐linearity and hysteresis. In dynamic measurement, the speed, acceleration and vibration of the vehicle produce little effect on the result, which can be neglected, thus being able to overcome the disadvantages of the traditional weighing method which is of low speed and great errors.

In a modern business environment, employees are a key resource to a company. Hence, the competitiveness of a company depends largely on its ability to treat employees fairly. Fairness can be attained by using the load‐balancing methodology. Develops an integer programming model for vehicle routing problems. There are two objectives, first, to minimize the total distance, and second, to balance the workload among employees as much as possible. We also develop a heuristic algorithm to solve the problems. The findings show that the proposed heuristic algorithm performs well to our 11 test cases.

In this paper, two omni‐directional mobile vehicles are designed and controlled implementing distributed mechatronics controllers. Omni‐directionality is the ability of mobile vehicle to move instantaneously in any direction. It is achieved by implementing Mecanum wheels in one vehicle and conventional wheels in another vehicle. The control requirements for omni‐directionality using the two above‐mentioned methods are that each wheel must be independently driven, and that all the four wheels must be synchronized in order to achieve the desired motion of each vehicle.

Distributed mechatronics controllers implementing Controller Area Network (CAN) modules are used to satisfy the control requirements of the vehicles. In distributed control architectures, failures in other parts of the control system can be compensated by other parts of the system. Three‐layered control architecture is implemented for; time‐critical tasks, event‐based tasks, and task planning. Global variables and broadcast communication is used on CAN bus. Messages are accepted in individual distributed controller modules by subscription.

Increase in the number of distributed modules increases the number of CAN bus messages required to achieve smooth working of the vehicles. This requires development of higher layer to manage the messages on the CAN bus.

The limitation of the research is that analysis of the distributed controllers that were developed is complex, and that there are no universally accepted tool for conducting the analysis. The other limitation is that teh mathematical models of the mobile robot that have been developed need to be verified.

In the design of omni‐directional vehicles, reliability of the vehicle can be improved by modular design of mechanical system and electronic system of the wheel modules and the sensor modules.

The paper tries to show the advantages of distributed controller for omni‐directional vehicles. To the author's knowledge, that is a new concept.

The purpose of this paper is to develop a new wheel control scheme for wheeled vehicle with passive linkage mechanism which realizes high step‐overcoming performance.

Developing wheeled vehicle realizes omni‐directional motion on flat floor using special wheels and passes over non‐flat ground using the passive suspension mechanism. The vehicle changes its body shape and wheel control references according to ground condition when it runs over the rough terrain.

Utilizing the proposed wheel control scheme, the slip ratio and the disturbance ratio of the wheel reduce when the vehicle passes over the step and its step‐overcoming performance is improved.

The paper's key idea is modification of its kinematic model referring to the body configuration dynamically and using this model for wheel control of the vehicle. The controller adjusts the wheel control references when the vehicle passes over the rough terrain changing the body shape and reduces the slippage and the rotation error of wheels.

According to the nature and source of alternative energy, types of new energy vehicle include hybrid electric vehicle, pure electric vehicle, fuel cell vehicles, natural gas vehicle, coal‐to‐alcohol vehicle, bio‐fuel vehicle, clean diesel vehicle and so on. At present, all kinds of new energy vehicle are flourishing, but in the near future it is not sure what kind of new energy vehicle that national policies will support, so the risk of new energy vehicle project is large. This paper aims to address this issue.

Grey target decision‐making mainly was used in the choice of programs. First, the decision‐making matrix and the index weight are determined after establishing the decision‐making index system; then the positive clout and the negative clout are determined; the distance to the positive clout and the negative clout for every decision‐making program are calculated; finally, the composite distance to clout is obtained and programs sorted in light of the size of composite distance to target centre.

This paper analyzed the operating conditions of new energy vehicle in Zhengzhou and Xinxiang; and then elaborated the modelling steps of weighted grey target decision with both the positive clout and the negative clout, and used in recent decision‐making the new energy vehicle in Henan Province. It not only makes more comprehensive and rational decision‐making, but also extends the application of the grey target decision model in practice.

In the recent two years of formulating national and local relevant preferential policies, the enthusiasm of enterprises to participate and the level of consumer awareness are further improved; as an international trend, the development of a new energy vehicle is inevitable.

It helps to make scientific decision‐making. The study proposes a theoretical guidance to carry out the new energy vehicle project in Henan Province.

This paper elaborates the modelling steps of weighted grey target decision‐making based on positive clout and negative clout, and established the model of grey target decision‐making according to the selected index; finally, it analyzes the recent development route of a new energy vehicle in Henan Province and puts forward some suggestions.

The objective of this paper is to evaluate the potential sustainable transportation strategies for Cairo in terms of their impact on emissions over the next ten years. The considered strategies include using cleaner fuel, implementing inspection and maintenance programs and adopting emission standards for new vehicles.

The strategies were evaluated in terms of the expected reductions of particulate matter (PM) and ozone precursors due to the future implementation. Emissions were estimated utilizing a mix of the relevant national and international. Accordingly, a three‐phase integrated strategy is recommended, considering the local technical and institutional aspects.

In case of no actions taken, emissions of PM and ozone precursors could increase at the year 2013 by 95 and 50 percent, respectively. Implementing the proposed integrated strategy could result in reducing the emissions of PM and ozone precursors by about 53 and 49 percent, respectively.

The proposed strategy is applicable because the targets are set considering the local aspects. However, the estimated emission reductions could almost compensate for the increase in the fleet size over the time. Therefore, achieving real reductions of emissions requires additional strategies to be considered.

Owing to the lack of local emission factors and measurements, this original work highlights the expected impacts of the potential strategies for controlling vehicle emissions in Cairo. Also, the findings indicate the need to consider other additional strategies in the long term planning process.